Air conditioner



FIG. 1 is a front perspective view of an air conditioner showing our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof; and,

FIG. 6 is a top view thereof.

The broken lines in the drawings illustrate portions of the air conditioner which form no part of the claimed design. 

CLAIM The ornamental design for an air conditioner, as shown and described. 